Proposal: Scala macros

[darrenoakey]

Just want something exactly the same as Scala macros - that allows you to change the ast at compile time. For example, if I could create a base class "Boring" such that if I did this:

class MyClass : Boring
{
    public readonly string a;
    public readonly string b;
}

it would

• generate a constructor that takes a and b
• and therefore compile without errors
• generate equals, testing and hash table

or I could create something like Cloneable

class Blah : Cloneable
{
     

}

which would add a clone method, which would rewrite the constructor and store any constructor parameters that aren't passed in, and then just call the constructor again with the same parameters

or I could create something like Locked

class Blah : Locked
{
     void Method1() {}
      string Method2() {return "hi"}
}

which would have an internal object _lockObject, and rewrite each of the methods as if I put lock (_lockObject) around the method body.

so far I haven't really found anything I wanted to do that I couldn't do in Scala macros - it somewhat obviates the need for a weaver.

[JoergWMittag]

While I am a huge fan of Scala, and think that more languages should steal from it, and I am a huge fan of macros, and think that more languages should have them, and I believe that Scala has tremendously advanced the state-of-the-art in statically-typed rich-syntax macros, the fact that macros were removed from the language, and re-introduced in an incompatible manner, in almost every major release over the last years, shows us that the state-of-the-art probably still needs some more advancing.

If you are advocating for "Scala macros", you at least should say which ones, since they have been re-designed multiple times.